Pumping mechanism



May 8, 1934. Q BAUR PUMPING MECHANI'SM Filed Nov. 12, 1929 4 Sheets-Sheet 1 lull/lus May 8, 1934. O. BAUR PUMPING MEGHANISM Filed NOV. 12 1929 4 Sheets-Shea*l 2 May s, 1934. Q BAUR PUMPING MECHANISM Filed Nov. 12, 1929 4 Sheets-Sheet 3 Y May 8, 41934.

vo. BAUR PUMPING MECHANISM Filed Nov. 12. 1929 4 Sheets-Sheet 4 '50 the blocks n bear Patented lMay 8, 1934 UNITED 'srArEsf Y PUMPING MECHANISM Ottmar Baur, Stuttgart, Germany,

assigner to VSiemens & llalake, Aktiengesellschaft, Simensstadt, near Berlin, Germany, a corporation of Germany Application November 12, 15529, Serial No. 406,708 In Germany Decemberl, 1928 The present invention relates to pumping mechanism of the type in which a plurality of plunger pumps'are arranged radially of a cam driving the same. The invention is particu- I larly applicable to fuel pumps for multi cylinder Diesel engines.- 4

According to the invention a simple arrang ment of this kind .is obtained by means of a carrier ring arranged concentric with the cam l shaft, in which ring the cylinder casings of the various pumps are radially inserted and secured and which contains a hollow, annular space filled with fuel into which opens the fuel feed pipe common to all the pumps and further the l suction passage and if desired also a return passage of each separate pump. 1

Two forms of construction of the invention as applied to-a fuel pump are illustrated in the ac' companying drawings in which:-' -v Figure 1 is a view, partly in section, of a fue pump installation for a nine cylinder aixship motor. Figure 2 is a section on'theline A--B of Fig'- ure 1.

Figure 3 shows partly in section a second form of construction, and

Figure 4 is-a section online C-l-D of Figure 3. In th'e first construction shown in Figure 1, a supporting or Vcarrier ring a is introduced betweenvr the fastening flange of a bearing cover c, supporting the crank-shaft b, andthe adjacent front side d of the crank casing. The bolts e by which the bearing cover is fastened on the crank case pass through the supporting ringand 40 passages i and k provided in the eynnder wens open into the annular-space f. The ports i and Ic are controlled by the pump pistons h.

The ends of the pump pistons projecting from the cylinders g are .constantly pressed by a spring m against a block n which is guided in a ring o concentrically arranged round the crank shaft. This guide ring o is castintegral with the supporting ring a by radial ribs p provided v between the separate pumps. The rollers q of agansta-cam r on the crank shaft. e .f

I. Near the outer end of Veach pump piston, a v g1-cove, or passage is cut 'in thesurface of the piston, and is adapted to form a return-passage for the fuel from the space abovethe piston to pipe connections leading to the injection nozzles cl cum, (ci. 12s- 139) the annular-'spacci by way of passage k when the piston reaches a predetermined position in `its outward stroke. The return groove communicates with the space above the piston, and-is provided with an obliquely cut wall or side s 60 adapted to cooperate with the port Ic and determine the position at which the port 7c isopened as the piston travels outwardly. Withthe piston in its lowermost position, fuel is. admitted tothe cylinder .g through ports Vi and Ic., `As the 05 piston is moved upwardly bythe cam 1', the ports i and Icare closed by the upper end of the piston h, and thel fuel above the piston is forced fr out of the cylinder and into the pipe 18 leading to the injection nozzle 16 of the appertaining 70 engine cylinder 17 as shown for' instance'in Fig. 4. As thepump piston continues on its` outward stroke, the oblique wall s of the return passage `on the cylinder and port k. The amount of fuel supplied by the pump on each stroke may be regulated by rotating the piston h to change the relative position of the groove surfaces with respect to the port Ic. In order to regulate the quantity of fuel supplied at each stroke, all thev pump pistons and thereby the controlling surfaces are angula'rly displaced in their cylinders. 85 This is effected by means of a spindle t mounted in the supporting ring andonwhich a bevel gear u is xed which meshes with a large crown gear o mounted on the guide ring o. A toothed segment gear w on each of the separate pumps meshes with the gear v. Each of the gears zo is clamped on` a sleeve whichis revoluble on the cylinder wall. A cross-piece z fast on'the piston so projects into a slot y in the sleeve that on the rotation of the sleeves by the adjusting device t, u, v, w, the pistons, together with theircontrolling surfaces, are also turned and thereby` the quantityeof fuel fed is altered.

' The supply of fuel to thehollow space f in the ringv a takes place through an inlet 1 0. The

of the engine are connected to the nipples 1l which are screwed coaxially with the cylinders into the supporting ring and lock them in position. The annular space f can be freed from air through'a screw 12 provided at its highest point.

The open sides of the annular space formed between the inner periphery of the supporting ring and the outer periphery of the guide-ring 110 Figures 3 and 4 is distinguished from that just itself, independently of the others, can be in described principally by the fact that the supporting ring a as well as the guide ring o are themselves cast in one piece with the bearing box cover and do not form a Ispecial piece. Further, kinthis second construction each individual pump as -a complete unit is inserted from the outside into the supporting ring so that each pump in serted or removed. On each adjusting sleeve :c a stop 15 is'secured; this is designed to ensure that in inserting or withdrawing the individual pumps the pistons remain in their cylinders and will not be forced out by spring m.

l I claim:

1. In aninjection pump for multi-cylinder engines, the combination of a supporting'ring, disposed concentrically with the main engine shaft,

and having an annularv fuel space, a plurality of pump cylinders supported radially in the inner and outer wall of said supporting ring across said fuel-space, and having intake and exhaust ports directly communicating with said annular space in said ring, each cylinder being provided with a piston for controlling said ports, and a fuel inlet passage connected to said annularl space.

2. An injection pump as specified in ciaim i, wherein the supporting ring is removably arranged between a. front wall of the engine casing and a cover for closing the front wall, and containing the main shaft bearing of the engine.

3. T he combination in an internal combustion engine.j having a crank-case, a plurality of cylinders mounted on said crank-case, and pumps on said crank-case for supplying fuel to said cylinders; of fuel ducts located entirely in the wall of the crank-case 'and connecting the pumps, and means for supplying fuel to the ducts.

4. The combination in an internal combustion engine having a. crank-case, a plurality of cylinders projecting outwardly from the crank-case, and pumps mounted on said crank-case for supplying fuel to said cylinders; of a continuous fuel passage in the crank-case wall extending around` the case connecting the pumps, and means for supplying fuel to the continuous passage.` 5. The combination in an internal combustion engine having a crank-case, anda plurality of cylinders mountedon said crank-case; of a continuous fuel passage located entirely in the crank-case wall' and extending around the case, 10G fuel pumps intersecting the fuel passage, and means for supplying fuel te the fuel passage.

6. The combination in an engine of the character described, having a crank-case, cylinders carried by the case, and fuel .pumps mounted in the case in spaced order; cf means entirely embedded in the wall of the crank-case for conveying liquid fuel from one pump to another, and means for supplying fuel to said conveying means.

o'rrMAR BAUR. 

